nvme-multipath: set bdi capabilities once

The queues' backing device info capabilities don't change with each
namespace revalidation. Set it only when each path's request_queue
is initially added to a multipath queue.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 6437f22..0624393 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1909,13 +1909,6 @@ static void __nvme_revalidate_disk(struct gendisk *disk, struct nvme_id_ns *id)
        if (ns->head->disk) {
                nvme_update_disk_info(ns->head->disk, ns, id);
                blk_queue_stack_limits(ns->head->disk->queue, ns->queue);
-               if (bdi_cap_stable_pages_required(ns->queue->backing_dev_info)) {
-                       struct backing_dev_info *info =
-                               ns->head->disk->queue->backing_dev_info;
-
-                        info->capabilities |= BDI_CAP_STABLE_WRITES;
-               }
-
                revalidate_disk(ns->head->disk);
        }
 #endif

diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 54603bd..9f28449 100644 (file)
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2017-2018 Christoph Hellwig.
  */
 
+#include <linux/backing-dev.h>
 #include <linux/moduleparam.h>
 #include <trace/events/block.h>
 #include "nvme.h"
@@ -666,6 +667,13 @@ void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id)
                nvme_mpath_set_live(ns);
                mutex_unlock(&ns->head->lock);
        }
+
+       if (bdi_cap_stable_pages_required(ns->queue->backing_dev_info)) {
+               struct backing_dev_info *info =
+                                       ns->head->disk->queue->backing_dev_info;
+
+               info->capabilities |= BDI_CAP_STABLE_WRITES;
+       }
 }
 
 void nvme_mpath_remove_disk(struct nvme_ns_head *head)